JP2002524817A - Device to perform power transformer function and immediate trip function - Google Patents

Abstract

(57) [Abstract] An instantaneous tripping power transformer particularly suitable for use in residential circuit breakers is one of transformers for supplying power to the electronic components of the circuit breaker while providing a main circuit breaker contact current path. Includes a high current main outer winding wound with one or more turns to act as a secondary winding. The transformer includes a secondary winding configured to power the electronics of the trip circuit. The secondary winding is wound in a substantially cylindrical shape and has a through hole. A main outer winding is wound around the outer surface of the secondary winding. A conductor electrically connected to the secondary winding supplies power to the trip circuit. A third or trip winding is located in the bore of the secondary winding and is configured to trip the circuit breaker under electronic control. The third winding is wound in a substantially cylindrical shape, and a conductor for the trip circuit is electrically connected to the third winding. A trip mechanism actuation plunger adapted to be driven by the main outer winding and / or the trip winding extends from one end of the third winding and is coupled to the breaker switch. ing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION

The present invention relates generally to circuit breakers, and more particularly, to power transformers having a small shape factor.

[0002]

BACKGROUND OF THE INVENTION

Arc detection is often performed to protect indoor wiring and consumer wiring, such as extension cords, home appliances cords and household appliances. Generally, when an arc is detected, it is desirable to open the circuit where the arc was detected. Although arc detection is desirable, certain known residential circuit breakers are large and expensive, and often cannot be used.

[0003] For example, one known residential circuit breaker that includes an integral arc detection device includes a separate power supply, sometimes referred to as a "pigtail," to provide power to the arc detection circuit and a separate overcurrent trip device. Typically, it is supplied. Such power supplies and trip devices can be physically large. To accommodate the power supply and trip device within the circuit breaker jacket, the circuit breaker housing is typically sized, for example, from a 0.5 inch shape factor housing to a 1.0 inch shape factor housing. Must be increased.

[0004] Depending on the size of the circuit breaker housing, such a circuit breaker may not be available, at least in some residential applications, due to space constraints. Furthermore, the size of the housing increases the cost of the circuit breaker.

It would be desirable to provide a power source and trip device for use in residential circuit breakers that perform the required functions but have relatively small physical dimensions. It would further be desirable to provide such a power supply and trip device that is simple to manufacture and inexpensive.

[0006]

SUMMARY OF THE INVENTION

An instantaneous trip power transformer particularly suitable for residential breaker applications includes a transformer, which in embodiments has a high current main outer winding conductor. The conductor of the main outer winding can be wound to have one or more turns, creating a main breaker contact current path. The conductor of the main outer winding also acts as a primary winding for a power transformer for supplying power to the electronic components of the circuit breaker.

A transformer configured to supply power to the electronic components of the trip circuit
Including the next winding. The secondary winding is wound to have a substantially cylindrical shape and has a through hole. The conductor of the main outer winding is wound around the outer surface of the conductor of the secondary winding. A conductor is electrically coupled to the conductor of the secondary winding and extends therefrom to supply power to the trip circuit.

A third or trip winding is located in the bore of the secondary winding and is configured to trip the circuit breaker under electronic control. Specifically, the third winding is wound so as to have a substantially cylindrical shape. A conductor is electrically coupled to the conductor of the third winding and then extends to the trip circuit. A conductive cylinder is disposed within the bore of the third winding, and a trip mechanism actuation plunger is disposed at least partially within the cylinder and extends from one end of the third winding conductor. A plunger is mechanically coupled to a spring-loaded switch that extends to the breaker main contact, as is well known.

Prior to operation, the conductor of the primary winding is electrically coupled between a power supply, eg, an AC power line, and the electronic components of the circuit breaker. The conductor of the secondary conductor is electrically coupled to and supplies power to the trip circuit, and the conductor of the third winding is electrically coupled to the electronic trip circuit.

In operation, current flows through the conductor of the primary winding, which acts as the main circuit breaker current path. The components of the trip circuit are supplied by utilizing the current induced from the conductor of the primary winding to the conductor of the secondary winding. In a normal trip condition, the trip circuit activates the third coil, for example, with energy stored in a capacitor. The DC magnetic field of the third winding conductor is superimposed on the AC magnetic field generated by the primary winding conductor. As a result, the plunger activates a mechanical spring-loaded switch.

When a large current flows through the conductor of the primary winding, for example, when a short circuit or the like occurs, the magnetic force of the magnetic field of the conductor of the primary winding trips the plunger to activate the magnetic field. The release plunger moves from a first inactive position to a second active position. When the plunger is in the operative position, the circuit breaker is "tripped". This tripping of the circuit breaker takes place without the need for any control signal from the tripping device. Rather, when high current conditions exist in the primary winding conductor, the plunger trips the main circuit breaker current path due to the increased alternating magnetic field force in the primary winding conductor.

[0012] The integral trip coil and power transformer described above perform the necessary functions of supplying power and instantaneous tripping of large currents, but still have the important advantage of small dimensions. Bring. Instead of using a 1 inch form factor housing for a residential circuit breaker, a smaller sized housing can be utilized. Further, the transformer is not difficult to manufacture and inexpensive.

[0013]

【detailed explanation】

The figure shows an integrated immediate trip power transformer 10 which constitutes one embodiment of the present invention. Although the transformer 10 is described herein in connection with a residential application, it should be appreciated that the transformer 10 can be utilized for non-residential applications. Further, the transformer 10 may be incorporated in a known circuit breaker or may be configured separately from a circuit breaker, and use of the device is not limited to any particular type of circuit breaker. .

The transformer 10 includes a high current main outer winding formed by the conductor 14. The main outer winding conductor 14 can be wound having one or more turns, creating a main breaker contact current path. The conductor 14 of the main outer winding also acts as a primary winding for the transformer 10 to supply power to at least some of the electronic components of the circuit breaker, for example, a trip circuit (not shown). Connection pad 16 is conductor 1
4 at both ends to facilitate connection of the transformer 10 to the primary power path.

The transformer 10 also includes a secondary winding 18 configured to supply power to the trip circuit electronics (not shown). In the illustrated embodiment, the secondary winding 18 is
It is formed by a conductor 20 wound in a substantially cylindrical shape and having a through hole 22 therethrough. The main outer winding conductor 14 is wound around the outer surface 24 of the secondary winding conductor 20. A conductor 26 is electrically connected to the conductor 20 of the secondary winding and extends therefrom to supply power to the trip circuit.

A third or trip winding 28 is concentrically disposed within the bore 22 of the secondary winding. The third winding 28 is configured to trip the circuit breaker under electronic control. Specifically, the third winding 28 is formed by the conductor 30 wound in a substantially cylindrical shape. Conductor 30 is in electrical contact with conductor 34 that is coupled to the trip circuit electronics (not shown). A conductive cylinder (not shown) can be positioned within the bore formed by the third winding 28, and the trip mechanism actuating plunger 32 is at least partially disposed within the cylinder. , The third winding conductor 30
From one end. Tripping plungers 32 are known.

To make the transformer 10, a cylindrical coil forming device (insulated type) can be used. Coil forming devices are well known. The second and third insulated conductors 20 and 30 are wound using a coil forming device (not shown), and the conductors 26 and 34 are electrically connected to the conductors 20 and 30, respectively. For example, conductors 20 and 30 may be insulated copper conductors.

More specifically, a third conductor 30 is wound on a coil forming device, and a second conductor 20 is then wound on the third conductor 30. In the preferred embodiment, a cylinder 36 is selected that is made of soft iron with low magnetic loss and has dimensions such that the cylinder fits inside the bore defined by the third conductor 30. In another embodiment, the cylinder can be made of laminated steel. In any case, the cylinder is mechanically connected to the housing and slides the insulated coil former over the cylinder. A cylinder magnetically couples between conductors 20 and 30 and plunger 32.

Next, the conductor 14 of the primary winding is wound on the second conductor 20. A plunger 32 made of soft iron or, in another embodiment, laminated (transformer) steel, is placed inside the cylinder. A plunger 32 is mechanically coupled to a spring-loaded switch, which extends to the main contacts of the circuit breaker, as is well known.

Prior to operation, the primary winding conductor 14 is electrically coupled between a power source, eg, an AC power line (not shown), and the electronic components of the circuit breaker (not shown). Is done.
A secondary conductor wire 26 is electrically coupled to and provides power to the trip circuit, and a third winding conductor 34 is electrically coupled to the electronic trip circuit to provide power to the transformer 1.
0 so that the control signal can be transmitted. Plunger 32 is mechanically coupled to a circuit breaker switch mechanism (not shown) that activates the switch.

In operation, current flows through the conductor 14 of the primary winding, which acts as the main circuit breaker current path. By using the current induced from the conductor 14 of the primary winding to the conductor 20 of the secondary winding, power is supplied to the components of the trip circuit. In a normal trip condition, the trip circuit activates the trip winding or third winding 28, for example, with energy stored in a capacitor (not shown). The DC magnetic field of the conductor 30 of the third winding is superimposed on the AC magnetic field generated by the conductor 14 of the primary winding. As a result, plunger 3
2 activates the circuit breaker switch.

When a large current flows through the conductor 14 of the primary winding, for example, when a short circuit or the like occurs, the tripping plunger 32 operates due to an increase in the magnetic force of the magnetic field of the conductor of the primary winding. Therefore, the plunger is moved to the switch closed position, that is, the plunger 3
2 from the inoperative position to the switch open position, that is, to the operating position of the plunger 32.
The current level at which the tripping plunger 32 moves from the inoperative position to the active position is selectable, and for a 15 amp or 20 amp circuit breaker, the high current is in the range of 110 to 170 amps. It is common to choose
When the plunger 32 is in the actuated position, the circuit breaker is “tripped”. This tripping of the circuit breaker takes place without the need for any control signal from the tripping circuit. Rather, when a high current condition exists in the conductor 14 of the primary winding, the increase in the alternating magnetic field force of the conductor of the primary winding causes the plunger 32 to trip.

In addition to the instantaneous trip described above, a control signal can be transmitted from the trip circuit to the conductor 30 of the third winding via the conductor 34. This control signal may be, for example, a high voltage level signal, which moves the plunger 32 from a switch closed position to a switch closed position. Therefore, when a short circuit or the like occurs, the transformer 10 can be tripped by an externally applied voltage from the tripping circuit, in addition to performing the trip immediately.

The integral trip coil and power transformer 10 provide the necessary functions, ie, supply power and instantaneously trip a large current, and are small in size. Instead of using a 1 inch form factor housing for a residential circuit breaker, a smaller size housing (eg, a 0.75 inch shape factor housing) can be used. Moreover, the transformer is neither difficult nor expensive to manufacture.

While only certain preferred features of the invention have been illustrated and described in the drawings, various modifications will occur to those skilled in the art. For example, instead of using a cylinder with a circular cross-section to provide magnetic coupling between the conductor and the plunger, a cylinder with a rectangular cross-section may be used.
It is therefore to be understood that the appended claims are intended to cover all such modifications that fall within the scope of the invention.

[Brief description of the drawings]

The figure is a schematic diagram of an integrated power transformer and trip device according to one embodiment of the present invention.

Claims (18)

[Claims] A main current outer winding comprising a conductor; and a secondary winding comprising a conductor wound in a substantially cylindrical shape and having a through hole. A winding wound at least partially around the conductor of the secondary winding;
Apparatus for performing a power transformer function and an immediate trip function having a third winding disposed inside a bore of a conductor of the secondary winding. 2. The system of claim 1, further comprising a conductor electrically connected to the conductor of the secondary winding and extending from the conductor of the secondary winding to supply power to a trip circuit.
The described device. 3. The third winding comprises a conductor wound in a substantially cylindrical shape and having a through hole therethrough, and further disposed in the third winding winding. The apparatus of claim 1 having a shaped cylinder. 4. The method of claim 1, further comprising at least partially disposed within said cylinder,
A trip mechanism operating plunger extending from one end of the third winding conductor;
4. The apparatus of claim 3, wherein said plunger is mechanically coupled to the breaker switch and is movable from an inoperative position to an active position. 5. The apparatus of claim 4, wherein said cylinder and said plunger comprise at least one of the group consisting of soft iron and laminated steel. 6. The apparatus according to claim 4, wherein said plunger is adapted to move from said inoperative position to said operating position when a large current flows through said main outer winding. 7. The apparatus of claim 1, wherein each of the high current main outer winding, the conductor of the secondary winding, and the third winding are each comprised of an insulated conductor. 8. An apparatus functioning in conjunction with a circuit breaker, comprising: a large current main outer winding which forms a main current path and serves as a primary winding for a power transformer; A secondary winding comprised of a conductor having a bore therethrough, wherein the main outer winding is at least partially wound around the conductor of the secondary winding, An apparatus having a third immediate trip winding disposed inside the bore of the secondary winding conductor. 9. The system of claim 8, further comprising a conductor electrically connected to the conductor of the secondary winding and extending from the conductor of the secondary winding to supply power to the trip circuit.
The described device. 10. The apparatus according to claim 8, wherein said third winding comprises a conductor wound in a substantially cylindrical shape and having a through hole. 11. The apparatus of claim 10, further comprising a cylinder disposed within a bore of said third winding. 12. A trip mechanism actuating plunger at least partially disposed within said cylinder and extending from one end of said third winding conductor, said plunger comprising a circuit breaker switch. 12. The apparatus of claim 11, wherein the apparatus is adapted to be mechanically coupled to and movable from an inoperative position to an active position. 13. The apparatus of claim 12, wherein said plunger is adapted to move from said inoperative position to said operating position when a large current flows through said main outer winding. 14. An apparatus for tripping a circuit breaker switch, comprising: a large current main outer winding which is constituted by a conductor serving as a main current path and serves as a primary winding for a power transformer;
A secondary winding comprising a conductor wound in a substantially cylindrical shape and having a through hole therethrough, wherein the conductor of the main outer winding is at least partially formed by the conductor of the secondary winding. And a third immediate trip winding disposed in the bore of the conductor of the secondary winding and extending from one end of the conductor of the third winding. A trip mechanism actuation plunger adapted to be coupled to the circuit breaker switch. 15. The main outer winding, the secondary winding conductor, and the third winding conductor are formed of one of the group consisting of iron and laminated steel with low magnetic loss. An apparatus according to claim 14. 16. The third winding is wound substantially cylindrically, has a through hole, and further includes a cylinder disposed in the third winding. Item 1
An apparatus according to claim 4. 17. The apparatus of claim 15, wherein said plunger and said cylinder are formed from one of the group consisting of soft iron and laminated steel with low magnetic loss. 18. The apparatus of claim 16, wherein said plunger and said cylinder are formed of one of the group consisting of soft iron and laminated steel with low magnetic loss.